Managed an hour or so in the workshop, this aft!

It's been a long time, but I've been a good boy, and finished all the upstairs spring cleaning.......

Realised, I should check the belt tension. Someone said, should be able to comfortably turn the belt to 90*, mid longest run. All was ok.
While I was in there, I stuck some reflector tape on the pulley.........

I got some interesting results.
Running free. Forward, 4940rpm. Reverse, 3585rpm.
Belt attached.
Low gear. Forward, 5085rpm. Reverse, 3760rpm.
High gear. Forward, 5190pm. Reverse, 3860rpm.
Machine spindle. High gear, 1850rpm. Low, 790rpm.
So...... The motor runs around 100rpm faster, when driving the spindle. And 100rpm faster still, in High gear!

It's all a mystery to me........
David D